What is a major risk factor for developing chronic obstructive pulmonary disease (COPD)?

Long-term smoking is a well-established major risk factor for developing chronic obstructive pulmonary disease (COPD). The inhalation of tobacco smoke introduces numerous harmful chemicals to the lungs, leading to inflammation, damage to lung tissue, and impaired airflow. Over time, these changes can result in conditions such as chronic bronchitis and emphysema, which are the two primary components of COPD. The chronic inflammation and structural changes in the lungs associated with smoking significantly reduce lung function and increase the risk of respiratory complications.

While other factors, such as lack of physical exercise, exposure to allergens, and genetic predisposition can influence respiratory health, they do not have the same direct and well-documented link to the development of COPD as long-term smoking does.